Plug Style Caps

Plug Caps

Plug Style Closures

Our fluted plug tube closures are designed to seal Labcon SuperClear® round bottom tubes and other brands of plastic or glass tubes to a liquid tight position. These closures are made from 100% virgin Class VI medical grade resin so you can be sure there is no contamination from the use of commodity grade plastics.


These closures are medical grade and are lot tested and certified free of detectable Nuclease, Endotoxin, and ATP contamination. Available in several colors for your color coding.

Plug Caps
Plug Caps

Safe Secure Seaing

These closures are made from a USP class VI resin to ensure your work is safe and repeatable. And like our dual position aspirating caps and overfit caps these closures will fit most brands of plastic and glass tubes.

Our fluted plug closures are packaged in Loose bags for ease of use or are available with our SuperClear® round bottom tubes.

Fluted plug seal closures feature a Class VI polyethylene resin that wil seal on most plastic and glass tubes. These caps include a internal flute design that ensures a tight seal on various tube dimensions from 12mm to 13mm. Can be used with both plastic and glass tubes.


Available in 12mm sizes that fit all standard glass and plastic tubes from 12mm to 13mm internal diameter. In natural, white, yellow, purple, orange, red, blue, and green colors. These polyethylene closures are not autoclavable.

Endotoxin Endotoxin Free (Non pyrogenic)
Product samples are exposed to endotoxin-free water and the resulting extraction fluid is tested for contamination using the kinetic turbidimetric Limulus Amoebocyte Lysate (LAL) assay protocol and USP guidelines. All products tested must display less than 0.05 EU/ml to be certified free of endotoxin.
RNase/DNase Nuclease Free (RNase/DNase)
Product samples are exposed to nuclease-free water and the resulting extraction fluid is tested for nuclease activity on commercially available 7.5 kb Poly(A) tailed RNA (1µg) and HindIII-digested DNA (1µg) with a one hour 37°C incubation in appropriate buffers. Results are visualized on an agarose gel with appropriate positive and negative controls. Extraction fluid samples must show no degradation of the nucleic acids by the extraction fluid has occurred for the product to be certified as RNase-free and DNase-free
ATP Adenosine Triphosphate (ATP)
Product sample surfaces are tested for the presence of adenosine triphosphate (ATP) using a controlled bioluminescence reaction to detect contamination. Luminescence data is compared to results generated by ATP-free surfaces and surfaces with known amounts of ATP as a positive control. The relative light units result must indicate less than 2 X 10-12 mg/µl of ATP for the product to be certified as ATP free.
USP Metals Heavy Metals Free
Heavy metals have been tested for using the prescribed USP method and confirmed to have levels lower than 1 part per million (1ppm)
BSE/TSE Bovine Spongiform Encephalopathy-Transmissible Spongiform Encephalopathy
These products contain resins that are processed under conditions proven to exceed the European Union standard as listed in the 22nd Commission Directive EC 98/16/EC of March 5th, 1998 as annexed to council Directive EC 76/768/EEC and further Amendment 419 Annex II of 12 June 2001.
USP Medical Grade (USP)
U.S Pharmacoepia Methods and Guidelines (U.S.P Class VI) are used if applicable. We only use medical grade resins and pre-test all resins for contaminants prior to use. Resins are compliant with FDA CFR title 21-177.1520, 178.3295, 178.3297.
Prop 65 California Prop 65
No Labcon manufactured disposables contain any of the “listed chemicals” as referenced in the California Safe Drinking Water and Toxic Enforcement Act of 1986, (Prop 65) as revised May 25, 2018.
Phthalates Phthalates & Oleamide
All our resins are medical grade and are certified free of Bisphenol A (BPA), Oleamide, DiHEMDA, and Phthalates.
SVHC Substances of Very High Concern & REACH
All Labcon products are compliant with RoHS Directive 2002/95/EC/-2011/65-2015/863, are free of Substances of Very High Concern (SVHC), and are EU REACH Regulation (EC) No 1907/2006 compliant.
USA Origin
These products are Made in USA and all components meet the requirements for US origin under the NAFTA agreement.
FDA U.S. FDA Registered
Labcon is a U.S. FDA registered medical device manufacturer. Our facility is registered by the U.S. government to comply with CFR21 GMP regulations for manufacturing medical devices.
CE CE Compliant
As applicable Labcon products meet the requirements for CE marking under regulation 2017/746.
ISO ISO 9001 Quality Registration
Labcon has been registered to the ISO 9001 quality management system standar since 1997 and maintains registration to ISO 9001:2015.
Material 100% Virgin Polyethylene
Grade Medical
Rating USP Class VI
Colors Natural, White, Red, Yellow, Orange, Blue, Green, Purple
Fits Most popular plastic and glass tubes 12mm to 13mm
Approved Use Medical, Research, Industrial, Food & Beverage
Lot Expiration 4 years
Bulk
Bulk Box

This package is easy to use and store. Caps are supplied in one bag inside a corrugated container.

FDA Registered

Labcon is registered by the U.S. Food and Drug Administration to manufacture medical devices.

Medical Grade Resins

Only 100% Medical Grade virgin polyethylene resins are used in our fluted plug closures. No recycled plastics or commodity grade resins.

Lab Tested

These closures are developed using our own in-house laboratory and tested in real centrifuges.

Certified Quality

Our products are made to ISO standards and we are audited every 6 months to ensure you continous quality.

Certificates Online

Real test certificates are available by lot for these closures for you to download from the certificates page.

Sustainability Built In

Our closures are designed from the beginning with sustainability in mind. Beyond simple recycling to real solutions.